Support devices for supporting implants or prostheses

ABSTRACT

A support element (S) for supporting implants (I), such as dental implants, the support element comprising a bar (S1) and a plurality of pins (S5) that are fitted to the bar (S1) and that are arranged parallel to one another, each pin (S5) defining a free end that is provided with reception means (S8) that are suitable for co-operating with the implant (S) so as to hold it on the reception means (S8) of the pin (S5), the bar (S1) including at least one mounting end (S4) for mounting the bar (S1) on another support device, thereby forming a support structure;the support element being characterized in that each pin (S5) is provided with a removal system (S9) for removing the implant (S) from the reception means (S8), without coming into contact with an exposed portion of the implant (S).

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a National Stage of International Application No.PCT/FR2016/052683 filed Oct. 18, 2016, claiming priority based on FrenchPatent Application No. 1560110 filed Oct. 22, 2015.

The present invention relates to tools, utensils, instruments, or moregenerally support devices for supporting implants or prostheses, such asdental implants, in order to handle them while subjecting them to asurface process. With such support devices, the implants may besubjected to a method of grafting bioactive polymer, such as poly sodiumstyrene sulfonate (PolyNaSS). Although the present invention is moreparticularly intended for dental implants for the purpose of graftingbioactive polymer, it may also be used with other types of implant forthe purpose of some other surface process or other process.

In the prior art, document EP 2 032 663 is known, which describes amethod of grafting bioactive polymer onto a prosthetic material made oftitanium or titanium alloy. That method recommends three successivesteps, namely:

-   -   generating free-radical-donating species at the surface of the        prosthetic material;    -   generating radicals at the surface of the prosthetic material by        thermal reactions; and    -   putting prosthetic material into contact with at least one        monomer carrying a function for enabling radical polymerization.        Radical polymerization of said monomer enabling the formation of        a bioactive polymer in the absence of oxygen.

Consequently, the method of document EP 2 032 663 is more particularlydirected to the physical or chemical reactions and interactions thatmake it possible to synthesize the bioactive polymer directly on thesurface of an implant. This gives the bioactive polymer thecharacteristic of being grafted in permanent manner on the implant. Thebioactive polymer is preferably PolyNaSS, and the type of oxidation ofthe implant is preferably chemical oxidation.

Although the method of document EP 2 032 663 outlines how to perform thegrafting method in a laboratory on a small scale, it gives absolutely noindication about how to apply the grafting method industrially on alarge scale.

Specifically, an object of the present invention is to use the method ofgrafting bioactive polymer industrially on a large scale. In otherwords, the grafting method is to be used in an industrial environment inorder to process large numbers of implants simultaneously. Althoughchemical oxidation is emphasized in the grafting method of document EP 2032 663, it quickly becomes clear in an industrial environment thatoxidation of that type (chemical) is entirely inappropriate, and indeeddangerous. The present invention has thus turned to anodic oxidation(anodizing), which is not mentioned in document EP 2 032 663.

It is precisely for the purpose of industrializing the grafting methodthat a plurality of support devices have been developed that enable theimplants to be handled easily.

In this context, the present invention firstly proposes a supportelement for supporting implants, such as dental implants, the supportelement comprising a bar and a plurality of pins that are fitted to thebar and that are arranged parallel to one another, each pin defining afree end that is provided with reception means that are suitable forco-operating with the implant so as to hold the implant on the receptionmeans of the pin, the bar including at least one mounting end formounting the bar on a support device, thereby forming a supportstructure.

Thus, the implant support element presents a general configuration thatis similar to the configuration of a comb, with a common bar from whichthe teeth project in parallel. The implant support element may begripped manually or mechanically via its bar, and more particularly viaits mounting end. The implant support element thus constitutes a baseelement that may be mounted on a plurality of support devices in orderto create a complex support structure.

In the invention, each pin is provided with a removal system forremoving the implant from the reception means, without coming intocontact with an exposed portion of the implant. In an advantageousembodiment, the removal system comprises a rotary ring that is mountedon the pin, the implant in engagement with the reception means cominginto contact with the rotary ring, such that one revolution of therotary ring causes the implant to disengage from its reception means.Preferably, each pin comprises a base that is fitted to the bar, thebase being surmounted by a rod having a free end that is provided with athread forming the reception means, the rotary ring being engaged aroundthe rod, bearing against the base, the threaded free end projecting outfrom the rotary ring in order to enable the implant to be screw-fastenedon the threaded free end, coming into abutment against the rotary ring.Thus, freely turning the rotary ring about the rod causes the implant tobe unscrewed from the threaded free end, so that the implant may bereleased from its support element. During the turning of the rotaryring, its vibration is transmitted to the implant that is in abutmentagainst the rotary ring. It should be observed that is it not necessaryfor the implant to be engaged fully on the threaded free end: itsuffices that the implant is screw-fastened on the threaded free endjust barely enough to hold it in position, given that it comes intoabutment against the rotary ring. As a result, turning the rotary ringjust a little suffices to unscrew the implant from the threaded freeend.

In another practical aspect, the bar supports about twelve pins, withthe pins at a spacing that lies in the range about 1 centimeter (cm) to2 cm. In addition, the bar may present a cross-section ofcircularly-cylindrical shape that is truncated in such a manner as toform a longitudinal flat that is arranged remote from the pins. Thus,the longitudinal flat serves as a bearing surface making it possible tostand the support element on a plane surface.

The invention also defines a mounting slab for mounting support elementsfor supporting implants, the mounting slab including a plurality ofmounting housings receiving the mounting ends of the bars of supportelements for supporting implants, as defined above. The mounting slabwith its implant support elements thus constitutes a complex supportstructure that makes it easy to handle a plurality of implant supportelements simultaneously.

In an advantageous aspect, the pins are arranged opposite ways roundrelative to one another. In addition, the mounting slab may also includea removable handle.

By way of example, the mounting slab may be used during the graftingmethod, more particularly during the cleaning, anodizing, and rinsingsteps.

The present invention also defines a mounting plate for mounting supportelements for supporting implants, the mounting plate including aplurality of mounting rails receiving the bars of support elements forsupporting implants as defined above. Once again, the mounting platefitted with implant support elements constitutes a complex supportstructure that may be used during the grafting method, particularlyduring the polymerization step.

Advantageously, the bars are engaged by sliding into an open access end,the pins being parallel and pointing in the same direction. In addition,the mounting plate may also include fastener means that are arranged ona face remote from the mounting rails for fastening the plate on anelevator carriage.

Still in the context of the invention, a washing rack is also definedcomprising a central pole that forms mounting housings that receive themounting ends of the bars of support elements for supporting implants asdefined above. Once again, the washing rack and its implant supportelements constitute a support structure that may be used during thegrafting method, and more particularly during washing and drying steps.

In a practical aspect, the support elements for supporting implants maybe arranged on either side of the pole in balanced manner,advantageously sloping. Furthermore, the central pole may be providedwith a handle.

As described above, the implant support element constitutes the baseelement that may be associated with other elements, such as the slab,the plate, or the rack, so as to constitute complex support structuresthat are used during certain steps of the grafting method. Once again,it should be understood that the elements are more particularly adaptedto being used during a method of grafting bioactive polymer, but theymay also be used for other types of processing method.

The invention is described more fully below with reference to theaccompanying drawings, which show several embodiments of the invention.

IN THE FIGURES

FIG. 1 is a very diagrammatic block diagram view showing the varioussteps of the grafting method of the invention;

FIG. 2 a is a perspective view of an implant support element of theinvention;

FIG. 2 b is a view of the FIG. 2 a implant support element with implantsmounted thereon;

FIG. 2 c is a large-scale vertical section view through an implantmounted on a pin of the implant support element in FIGS. 2 a and 2 b;

FIG. 3 is a perspective view of a mounting slab for implant supportelements that has already received three implant support elements andthat is ready to receive a fourth element.

FIG. 4 is a perspective view of a container filled with inert gas inwhich the mounting slab with its implant support elements is placed;

FIG. 5 a is a diagrammatic perspective view of a chamber used for thepolymerization step;

FIG. 5 b is a large-scale perspective view of a detail of FIG. 5 a;

FIG. 6 is a perspective view of a mounting plate in which the implantsupport elements are received by sliding;

FIG. 7 is a diagrammatic plan view of the polymerization stationarranged inside the polymerization chamber;

FIGS. 8 a to 8 e show various embodiments of a polymerization vesselcontaining the monomer;

FIGS. 9 a and 9 b are perspective views of another embodiment of thepolymerization station;

FIGS. 10 a and 10 b show two variants of vessels receiving the device inFIGS. 9 a and 9 b;

FIG. 11 is a perspective view of a washing rack of the invention;

FIG. 12 a shows a bracket for anodizing two femoral hip implants;

FIG. 12 b shows a femoral hip implant arranged in a container filledwith inert gas;

FIG. 12 c shows a strip on which the femoral hip implants are mounted;

FIG. 12 d shows two strips engaged in mounting rails of the elevator ofthe polymerization station; and

FIG. 12 e shows a washing tray for femoral hip implants.

Reference is made firstly to FIG. 1 in order to describe the varioussuccessive steps of the method of grafting a bioactive polymer, such asPolyNaSS, on implants, in particular implants made of titanium ortitanium alloy, in order to achieve a non-stick or “non-cling” coatingon which bacteria and other infectious agents slide so that they cannotdevelop thereon.

The major successive steps are as follows:

-   -   a) mounting implants on an implant support structure: a support        element for dental implants and a support bracket for femoral        hip implants are described below;    -   b) dipping the implants (mounted on their support) into a bath        of acid, such as nitric and/or hydrofluoric acid, so as to clean        them: the immersion time may lie in the range about 30        seconds (s) to 1 minute (min);    -   c) rinsing the implants, e.g. with water;    -   d) dipping the implants (mounted on their support) in an        anodizing bath, e.g. based on orthophosphoric acid, so as to        anodize them and thus create titanium peroxides on their        surfaces: the dipping time may lie in the range about 10 s to 1        min;    -   e) rinsing the implants, e.g. with water;    -   f) putting the implants (still mounted on their support, or on        some other support, or on no support) into a gastight        polymerization chamber filled with inert gas, such as argon:        some other inert gas could also be used.    -   g) mounting the implants (mounted on their support, or on some        other support, or on no support) on an elevator installed in the        gastight chamber;    -   h) actuating the elevator so as to dip the implants into a        polymerization bath, e.g. a bath of monomer, such as sodium        styrene sulfonate (NaSS), present in the chamber;    -   i) subjecting the polymerization bath to a polymerization        catalyst, e.g. a thermal or UV catalyst, so as to synthesize        bioactive polymer on the surface of the implants, and thus        obtain an implant coated with a layer of grafted polymer, e.g.        PolyNaSS;    -   j) raising the elevator so as to extract the coated implants        from the polymerization bath;    -   k) removing the implants from the elevator;    -   l) extracting the implants from the gastight chamber;    -   m) washing the implants, e.g. by spraying pure water, so as to        remove any excess non-grafted bioactive polymer therefrom; and    -   n) drying the grafted implants.

In addition to these major steps, the method also defines intermediate,secondary, and/or optional steps that further improve the major steps,or that make it easier to handle particular implants, such as dentalimplants or femoral hip implants, for example. In particular, mentioncan be made of the following steps.

For dental implants:

-   -   a intermediate step a1—between step a- and step b- that consists        in mounting a plurality of implants on support elements that are        themselves mounted on a support slab that advantageously        includes a removable handle, the slab together with its implant        support elements constituting an implant support structure;    -   during steps b- to f-, the implants are handled by means of the        support slab, with the implant support elements mounted thereon;    -   an intermediate step e1—between step e- and step f- that        consists in placing the support slab with its implant support        elements in a container filled with inert gas, such as argon,        that is advantageously provided with a gastight lid, the        container then being put, during step f-, into the gastight        chamber filled with inert gas, such as argon, the container then        being opened so as to extract the support slab therefrom,        together with its implant support elements;    -   an intermediate step f1—between step f- and step g- that        consists in removing the implant support elements from the        support slab, then in mounting the implant support elements on a        support plate that is then mounted on the elevator, or, in a        variant, an intermediate step f2—between step f- and step g-,        step f2—consisting in mounting either the support slab (B) or        the support elements (S) on vertical axial rods (C) of the        elevator (L′) that are rotated in the polymerization bath;    -   an intermediate step k1—between step k- and step l- that        consists in removing the implant support elements from the        elevator, then in mounting the implant support elements on a        central pole that forms mounting housing for the implant support        elements in order to form a washing rack that is then extracted        from the chamber. The washing rack may also be formed at the        outlet of the gastight chamber; and    -   during steps m- and n-, the implant support elements are        configured in the form of the washing rack.

For femoral hip implants:

-   -   an intermediate step a2—between step a- and step b- that        consists in mounting a plurality of implants (H) on a support        bracket (Th), the implants (H) being handled, during steps b- to        f-, by means of the support bracket (B);    -   an intermediate step f3—between step f- and step g- that        consists in mounting the implants side-by-side on a strip that        is then mounted on the elevator;    -   during step the implants are on the strip; and    -   during steps m- and n-, the implants are arranged on a washing        tray.

By way of example, this method of grafting active polymer is now used ondental implants for which tools, accessories, or instruments have beendeveloped, enabling handling to be easier, quicker, and on a largescale.

FIGS. 2 a, 2 b, and 2 c show a support element S for implants, such asdental implants I. One type of implant I can be seen more particularlyin section in FIG. 2 c . It can be seen that the implant I comprises ahead I1 at its top end, and an annular bottom edge 12 at its oppositeend. The implant I defines a hollow inside 13 that presents a threadedwall 14. This design is entirely conventional for a dental implant. Thesupport element S includes a bar S1 on which there are mounted aplurality of pins S5 that advantageously extend parallel to one another.By way of example, it is possible to provide twelve pins S5 that arearranged in alignment and in parallel on a bar S1, with the pin axes ata spacing that lies in the range about 1 cm to 2 cm. In an advantageousembodiment, the bar is cylindrical presenting a cross-section that iscircular and truncated at its base in such a manner as to form alongitudinal flat that is arranged remote from the pins S5. This can beseen more clearly in FIG. 3 . The bar S1 includes at least one mountingend for mounting the bar on a support structure that is defined below.The mounting end S4 may even present a hollow housing. Each of the pinsS5 comprises a base S6 that is fitted to the bar S1, and a rod S7 thatis mounted on the base S5, defining a bottom diameter and including afree end that is provided with a thread S8. A shoulder is thus formed atthe top end of the base around the rod S7. Each pin S5 is furtherprovided with a rotary ring S9 that is engaged around the rod S7,bearing against the base S5. The threaded free end S8 projects out fromthe rotary ring S9 in order to enable the implant I to be screw-fastenedon the threaded free end, coming into abutment against the rotary ringS9, as shown in FIG. 2 c . It can clearly be seen that the threaded freeend S8 is engaged with the internal thread 14 of the hollow housing 13of the implant I. It suffices that the implant I is screw-fastened onthe threaded free end S8 just barely enough to guarantee it is held onthe rod S7, bearing against the rotary ring S9. Support elements S withthe implants I mounted thereon, as shown in FIG. 2 b , present thegeneral configuration of a comb, with teeth constituted by pins S5 onwhich the implants I are mounted.

In the invention, the rotary rings S9 constitute a removal system forremoving the implants from the reception means of the support elementconstituted by the threaded free ends S8. Specifically, by causing therotary rings S9 to turn freely about the rods S7, the implants I loosenand unscrew from the threaded top ends S8, and this without any need tocome into contact with the implants I, and in particular with theirexposed portions. In other words, the rotary rings make it possible tounscrew the implants without needing to touch them. It is advantageousfor the rotary rings S9 to be well aligned, so that it is possible totake action in common simultaneously on all of the rotary rings, so asto unscrew all of the implants I simultaneously from an implant supportelement S. By way of example, it is possible to envisage a rectilinearrod that is put into bearing contact with all of the rotary rings S9,and to which a rapid back and forth movement is imparted, making itpossible to unscrew the implants I. The implants I can then fall bygravity into a collection container. Clearly, the removal operation forremoving the implants I takes place only at the end of the graftingmethod, after the drying step n.

In place of the rotary rings, it is possible to envisage some otherremoval system that, by way of example, uses clamping by frictionimparted by resilient means so as to be able to undo the clamping, e.g.by vibration. It is also possible to envisage bonding the implant on thepin with an adhesive that releases when subjected to vibration, heat, asolvent, etc. In order to hold/remove the implants, provision can alsobe made to use magnetic attraction/repulsion.

Without going beyond the ambit of the invention, it is also possible toenvisage that the implants I do not have an internal thread 14, and thatthe bar S1 and the pins S5 are hollow so as to make it possible togenerate suction that pulls the implants I against the free ends of therods S7. By way of example, suction may be created at the mounting endS4. In this configuration, it is not necessary to provided rotary ringsS9. Stopping suction also constitutes a removal system. However,applying suction is more complicated to implement, which is why the useof rotary rings S9 is simpler to perform and more effective.

FIG. 3 shows three support elements S mounted on a mounting slab B thatincludes a plurality of mounting housings B1 in which the mounting endsS4 of the support elements S are received and advantageously blocked bymeans of blocking screws B2. FIG. 3 also shows a fourth support elementS that is ready to be received in its still-free mounting housing B1.Thus, four support elements S can be mounted on a mounting slab andarranged opposite ways round. Specifically, the two uppermost supportelements S are arranged with their pins S5 facing downwards, while theother two support elements S mounted at the bottom are arranged withtheir pins S5 facing upwards. In the invention, the mounting slab B isprovided with a removable stick-shaped handle B4 that makes it easy tohandle the mounting slab B with its support elements S mounted thereon.

In particular, it is possible to use the mounting slab B with itsremovable handle B4 during steps a- to e- of the method of graftingbioactive polymer. It is even possible to use the mounting slab B withits removable handle B4 so as to arrange the mounting slab B with itssupport elements S in the container filled with inert gas, such asargon. This can be seen in FIG. 4 . The removable handle B4 needs to beremoved, so as to leave its mounting housing B3 visible in the slab B.The container R may be closed by means of a lid R1: however, this isoptional since argon is heavier than air and remains in the container Reven in the absence of a lid. Thus, the mounting slab B with its foursupport elements S are put inside the polymerization chamber E that isfilled with inert gas, such as argon, by being put into the container R.Inside the chamber E, the lid R1 can be removed and the mounting slab Bwith its support elements S can be extracted from the container R.

The polymerization chamber E can be seen in FIG. 5 a . This type ofchamber is commonly referred to as a “glovebox” because of the presenceof gloves that make it possible to perform handling inside the chamber Ethrough a transparent wall E3. Although not shown, the chamber E isprovided with treatment means for treating its inside atmosphere, inorder to guarantee optimum pressure, purity, and/or humidity conditions.The most commonly used gas is argon, although other gases may also beused. The chamber E is mounted on a stand E4 and includes an inlet airlock E1 through which the containers R pass so as to arrive inside thechamber E. In conventional manner, the air lock E1 includes an inletdoor and an outlet door in order to be able to control the atmospherethat exists inside the air lock E1.

The polymerization chamber E contains a polymerization station K wherethe implants I are dipped in a polymerization bath so as to make itpossible to synthesize bioactive polymers (e.g. PolyNaSS) on theanodized surface of the implants, from an appropriate monomer X, such asNaSS. The polymerization station K includes an elevator L that ismovable vertically above a vessel T that is filled with monomer X, so asto dip the implants I into the polymerization bath of the vessel T andextract them therefrom. The polymerization station K advantageouslyincludes catalyst means so as to accelerate polymerization on theimplants dipped in the bath. The catalyst means may be in the form of a“bain-marie” tank M that is filled with liquid O that is heated byheater means M1, as can be seen in FIG. 6 . The catalyst means may alsotake the form of a UV radiation source, as described below.

With reference simultaneously to FIGS. 5 b , 6, and 7, it can be seenthat the elevator L includes a carriage L1 that is movable verticallyand that is mounted on a vertical rack L4 so as to make it possible tomove the carriage L1 vertically down and up. The movable carriage isprovided with mounting means that are suitable for receiving an implantsupport structure, as described below. By way of example, the mountingmeans may include a plurality of slideways L2 into which fastener meansP4 of the support structure can be inserted by sliding. The slideways L2form access openings on a front face that faces towards the gloveboxgloves E2. The elevator L may optionally be provided with a lid L3 thatcovers, advantageously in leaktight manner, both the vessel T filledwith monomer X and the bain-marie tank M filled with heated liquid O.

When the grafting method of the invention is applied to dental implants,and more particularly to support elements S as described above, amounting plate P is provided that includes, on one of its faces, aplurality of mounting rails P1 that receive the bars S1 of the supportelements S by sliding them into an open access end P2, as can be seen inFIG. 6 . The support elements S may thus be received one behind another,and one beside another, in the mounting rails P1 of the mounting plate Puntil it is full. The pins S5 with their implants mounted thereonproject out from the mounting rails P1. The mounting plate P is thenturned upsidedown, and it may be mounted in the slideways L2 of thecarriage L1 by means of one or more fastener lugs P4. In this way, themounting plate P is fastened and arranged below the carriage L1. Theelevator L may then be lowered, so as to dip the implants I into thebath of monomers X. The polymerization time lies in the range 2 hours(h) to 15 h as a function of the catalyst means used.

In a handling detail, the support elements S are removed from thesupport slab B while they are inside the chamber E, so as to be mountedindividually in the mounting rails P1 of the support plate P.

By way of example, the vessel T in FIG. 7 that contains the monomer Xmay present a box shape, with a flat bottom Tf and four side walls Tp.With catalyst means in the form of a “bain-marie” tank M, thisembodiment suffices. In order to make the temperature inside the tank ofthe vessel T uniform, flow-generator means may be provided, e.g. astirring device.

FIGS. 8 a to 8 e show, in very diagrammatic manner, a plurality ofvariant embodiments for a vessel filled with monomer X, and havingcatalyst means that are in the form of UV radiation sources. In FIGS. 8a and 8 b , the vessel T¹ presents a flat bottom Tf¹, but presents aside wall Tp¹ that is elliptical in shape. Two UV radiation sourcesS_(UV) are arranged one facing the other on the major axis of theellipse, as shown in FIG. 8 b . The elliptical shape of the side wallTp¹ makes it possible to improve propagation of the UV radiation throughthe monomer, particularly when the side wall Tp¹, and possibly also thebottom Tf¹, are reflective. By way of example, it is possible to providea vessel T¹ made of stainless steel with a mirror finish. It is alsopossible to provide a reflective silvered coating inside the vessel T¹.

FIG. 8 c shows a variant in which the vessel T² presents a wall Te inthe shape of a dish or a trough, without a flat bottom. By way ofexample, it may correspond to a semi-circular ellipsoid. Two UVradiation sources S_(UV) are also arranged one facing the other on themajor axis of the ellipsoid, as in the embodiment in FIGS. 8 a and 8 b.

FIG. 8 d shows yet another variant embodiment in which the vessel T³ ismade up of a plurality of elliptical reflectors Tr that are connectedtogether by connection segments Tl. The side wall of the vessel T³ thuspresents a complex shape. Each reflector Tr is provided with a UVradiation source S_(UV). The side wall may be reflective, without amirror finish or a silvered coating.

FIG. 8 e shows another variant in which the vessel T⁴ is box shaped,with a flat bottom Tf⁴ and side walls Tp⁴. One or more of the walls maybe constituted by a UV panel. It is even possible to envisage that theentire vessel T⁴ is constituted by five UV panels that are connectedtogether.

Reference is made to FIGS. 9 a, 9 b, 10 a, and 10 b in order to describea second embodiment for a carriage L1′ that can be used in the contextof the present invention. The carriage L1′ may be used in place of theabove-described carriage L1 that is arranged inside the gastight chamberE. While the implants I are static in the vessel when the carriage L1 isin its low position, the implants I mounted on the carriage L1′ aremovable inside the vessel when the carriage L1′ is in its low position.With reference to FIGS. 10 a and 10 b , it can be seen that the twoversions of vessels T⁵ and T⁶ present a shape that is substantiallycylindrical with UV radiation sources distributed over theirperipheries. The vessel T⁵ thus includes eight UV sources S′_(UV) thatare distributed in equidistant manner all around the vessel. The sourcesS′_(UV) may present an axial extent that is large. The vessel T⁶ isprovided with a plurality of optical endpieces Y to which there areconnected optical fibers Fo that are connected to a UV source (notshown). In view of the large number of endpieces Y and of optical fibersFo, the inside of the vessel T⁶ is irradiated in completely uniformmanner. The inside wall of the vessels T⁵ and T⁶ may be reflective forUV radiation.

In FIGS. 10 a and 10 b , the carriage L1′ is shown in its low position,in which it is inserted fully inside the vessels T⁵ and T⁶. In thesefigures, it is not shown how the carriage L1′ is moved axially in avertical direction, but any appropriate means can be used.

Reference is made below to FIGS. 9 a and 9 b in order to describe indetail the structure and the operation of the carriage L1′. In thisembodiment, it is designed to receive support elements S as describedabove, but it could also be envisaged that support slabs B provided witha plurality of support elements S are received by the carriage L1′. Inthe particular configuration in FIGS. 9 a and 9 b , each support elementS is mounted via its mounting end S4 at the free end of a vertical axialrod C that forms the rotary shaft of a horizontal wheel G. Each wheel Gis provided with a top disk G1 through which the top end of the verticalaxial rod C passes. In FIGS. 9 a and 9 b , the horizontal wheels G aresix in number, but this number is not limiting. The horizontal wheels Gare arranged inside a circularly-cylindrical collar F that is toothedinternally at F1. Teeth G1 of the horizontal wheels G are engaged withthe teeth F1 of the circularly-cylindrical collar F. The outer edge ofeach disk G2 bears against the circularly-cylindrical collar F. Inaddition, the toothed wheels G are also engaged with a central drivewheel N that is also toothed at N1. The top portion of the central wheelN is provided with a drive lug J for coming into engagement with rotarydrive means (not shown). At its bottom end, the drive wheel N isprovided with a hub Q that extends between the vertical axial rods C andthe support elements S. Advantageously, the hub Q is reflective, veryparticularly to UV radiation. By way of example, it is possible to makethe hub Q with reflective facets Q1. Although not shown, the carriageL1′ may be provided with a cover that hermetically covers the horizontalwheels G and the circularly-cylindrical collar F.

With such a design, it can easily be understood that turning a drive lugJ causes the drive wheel N to turn about its own axis. Given that thedrive wheel N is in meshed engagement with the horizontal wheels G, thehorizontal wheels turn both about their own axes, and also about thedrive wheel N inside the circularly-cylindrical collar F. Consequently,the support elements S both turn about respective axes that pass via therods C and their bars S1, and also revolve about a central axis thatpasses via the drive lug J, the drive wheel N, and the hub Q. Thesupport elements S thus perform complex motion resulting from thecombination of turning about their own bars and a revolving about thecentral drive wheel N. In this way, the implants I mounted on thesupport elements S move along complex paths inside the monomer presentin the vessel. It is thus guaranteed that the implants I are exposed inidentical and uniform manner to the UV radiation that irradiates themonomer present in the vessel.

With an elevator L′ associated with a vessel irradiated by UV radiation,such as the vessels T⁵ and T⁶, a grafted coating of bioactive polymer,such as PolyNaSS, is obtained with the desired thickness and density.The time needed for satisfactory polymerization may be considerablyshortened relative to polymerization with a thermal catalyst (of the“bain-marie” type), which is about 15 h. Specifically, it is easy toshorten the time by half, and by even more with UV radiation and avessel that are optimized, so as to reach a time that lies in the rangeabout 2 h to 5 h, or even less, of about 1 h.

Once grafting has been achieved, the implants are extracted from thevessel by raising the carriage L1 or L1′. The support elements S maythen be removed from the carriage by handling them by means of theglovebox gloves E2. They may thus be put into the inlet air lock E1 fromwhere they are extracted from the gastight chamber E. They may then besubjected to the steps of washing, so as to remove any excess graftedbioactive polymer, and drying.

FIG. 11 shows another utensil or instrument that makes it possible toadvantageously handle support elements S during the washing and dryingsteps. The utensil may be referred to as a washing rack D, given that itpresents a configuration that is close to the configuration of racksthat are found in dishwashers. The washing rack D includes a centralpole D1 that forms a plurality of mounting housings D2 in which themounting ends S4 of the support elements S are received. Optionalblocking screws D3 may be provided so as to block the mounting ends S4inside the mounting housings D2. The central pole D1 may also beprovided with a loop-shaped handle D4 via which the washing rack D canbe gripped manually. In FIG. 11 , twelve support elements S can becounted, namely six on each side of the central pole D1. It should beobserved that the support elements S are arranged to slope by about 45°relative to the horizontal or the vertical. The slopes of the supportelements S on either side of the central pole D1 are opposite, or offsetby 90°. Specifically, the implants I visible below the central pole D1in FIG. 11 point towards the left, while the implants I arranged abovethe central pole D1 point towards the right.

The washing rack D can thus easily be arranged in an appropriate washingappliance, into which water, preferably highly purified water, issprayed over the implants I, in order to remove any excess graftedbioactive polymer therefrom. The washing stage is followed by a dryingstage that may be performed in the same washing appliance.

At the end of the drying step, the rack D is extracted from thewashing/drying appliance, and the support elements S are removed fromthe central pole D1. Then, the implants I may be removed from eachsupport element S, as explained above, by turning the rotary rings S9 inorder to unscrew the implants I from the threaded ends S8. Without goingbeyond the ambit of the invention, it is also possible to envisage thatthe implants I are held by suction on appropriate support elements.

The description above refers to a particular type of implant, namelydental implants I. However, the invention is not limited to thatparticular type of implant, and other types of implant may be processed,coated, and handled in accordance with the invention. With reference toFIGS. 12 a to 12 f , reference is made to another type of implant,namely a femoral hip implant H. It is also possible to refer to afemoral prosthesis. In typical manner, the insert H comprises a femoralpin H1 for being inserted and sealed in the femur, and a neck rod H2 forreceiving the femoral head that is received in the acetabular cupfastened to the pelvis. The femoral prostheses H processed in thisembodiment do not have heads.

FIG. 12 a shows a first support device in the shape of a bracket Th thatmakes it possible to receive two femoral implants H. More precisely, thebracket Th includes two reception sleeves T1 respectively receiving theneck rods H2 of the implants H. The sleeves T1 are mounted on a commonplate that is provided with a mounting rod T3. The two sleeves T1 arealso provided with electric wiring means T4 for supplying the inserts Hwith electricity. The bracket Th may be used during steps b, c, d, and eof the grafting method. The bracket Th constitutes an implant supportstructure, like the above-described support element S, support slab B,and support plate. The bracket Th may be mounted on an elevator by meansof its mounting bar T3 so as to perform the cleaning, anodizing, andrinsing steps.

Once the steps have terminated, the implants H may be removed from thebracket Th and placed individually or as a group in a container R, suchas the container used above for the dental implants. The container R isadvantageously filled with an inert gas, such as argon, and it isoptionally provided with a lid R1. The implants may thus be put into thepolymerization chamber E through the inlet air lock E1. Inside thechamber, the implants H may be mounted on a strip V, as can be seen inFIG. 12 c . The strip V includes reception holes V1 in which the neckrods H2 are force fitted. The strip V also includes two oppositelongitudinal flanges V2 that make it possible to slide the strips V intoslideways L2 of the carriage L1 of the elevator L, as can be seen inFIG. 12 d . The implants H may thus be dipped into the vessel filledwith monomer X. After sufficient polymerization time, the implants maybe extracted from the vessel and the strips V may be extracted from theslideways L2. The implants H may then be removed from the strips V andextracted from the gastight chamber E through the inlet air lock. In avariant, the implants H may be mounted on the vertical axial rods C ofthe elevator L′. It can also be envisaged to mount a plurality ofimplants H on a single vertical axial rod C by using a supportstructure, such as the bracket Th.

For the subsequent washing and drying steps, a washing tray W isprovided (FIG. 12 e ) on which the grafted implants may be arranged. Thewashing tray W comprises two end flanges W1 that are connected togethervia two separator rakes W2 and two support rods W3. The implants H maythus be arranged between the teeth of the rakes W2 and bear against thesupport rods W3.

It should be observed that certain particular aspects associated withhandling femoral implants H may be protected independently of othercharacteristics described above, and could as a result be the subject ofdivisional applications. More particularly, the bracket Th, the strip V,and the washing tray W could be the subject of their own patentapplications.

The invention thus provides a method of grafting bioactive polymer ontoimplants that may be performed industrially on a very large scale. Theutensils that have been designed, such as the support element S, thesupport slab B, the support plate P, the washing tray D, the supportbracket Th, the strip V, and the washing tray W make it possible tooptimize the grafting method on an industrial scale. Finally, thegastight chamber E, and more particularly its carriage and its vesselmake it possible to perform the polymerization step on a large scale.Implants, in particular dental and hip implants, may thus be coated witha bioactive polymer, such as PolyNaSS, on a large scale and at a highrate.

The invention claimed is:
 1. A support element for supporting implants,the support element comprising a bar and a plurality of pins that arefitted to the bar and that are arranged parallel to one another, eachpin defining a free end that is provided with reception means that aresuitable for co-operating with the implant so as to hold it on thereception means of the pin, the bar including at least one mounting endfor mounting the bar on another support device, thereby forming asupport structure; wherein each pin is provided with a removal systemfor removing the implant from the reception means, without coming intocontact with an exposed portion of the implant; and wherein the removalsystem comprises a rotary ring that is mounted on the pin, the implantin engagement with the reception means coming into contact with therotary ring, such that one revolution of the rotary ring causes theimplant to disengage from its reception means.
 2. A support elementaccording to claim 1, wherein each pin includes a base that is fitted tothe bar, the base being surmounted by a rod having a free end that isprovided with a thread forming the reception means, the rotary ringbeing engaged around the rod, bearing against the base, the threadprojecting out from the rotary ring in order to enable the implant to bescrew-fastened on the thread, coming into abutment against the rotaryring.
 3. A support element according to claim 1, wherein the barsupports about twelve pins with the pins at a spacing that lies in therange of 1 cm to 2 cm.
 4. A support element according to claim 1,wherein the bar presents a cross-section of circularly-cylindrical shapethat is truncated in such a manner as to form a longitudinal flat thatis arranged remote from the pins.
 5. The support element according toclaim 1, wherein the implants are dental implants.
 6. The supportelement according to claim 1, wherein one revolution of the rotary ringalso causes the implant to detach from the pin by gravity alone.
 7. Thesupport element according to claim 1, wherein the rotary ring, whenassembled, has an exposed circumferential surface configured to engage amember that causes rotation of the rotary ring.